USA Today has just recently published a small article about The Ballad of Gay Tony. Along with the same information we've heard for a while, the article contains a new screenshot, some quotes from Rockstar Games co-founder Dan Houser, and the following details about missions (including the parachuting mission, which we'll probably be seeing clips of in today's trailer):

Packed with action set pieces à la films such as Mission: Impossible and Bad Boys, Gay Tony has Luis at one point parachuting from a helicopter onto a glass-windowed skyscraper. Inside he blasts his way to his prey a few floors below and shoots his target, who then topples out of the bullet-ridden window. Luis dives out after him, wearing a parachute that glides him to safety.

In another scene, Luis drops on to the top of a moving subway train from a bridge and unhooks one of the cars for a maniacal high-rolling collector of one-of-a-kind artifacts. A Skyhook chopper airlifts the freed subway car away.

So in case there was still any speculation, the parachuting is definitely confirmed! Now the only question that remains is whether or not the parachuting feature will be available outside this particular mission.

The article also sheds some light on the overall plot of the DLC:

The drug-addled Tony, losing a grip on his empire, puts Luis in dangerous circumstances in an attempt to retain his power.

...

Luis is torn between friends and family and his quest for power and riches. But as he climbs higher in Liberty City's social circles, he discovers that the upper crust has some issues.

it better not be a shotgun!! that would be pointless because TLAD already added 2 new shotguns, one of which is pointless. The assault shotgun is stupid in my opinion, but the sawed off one is sick!! I think they should've added some other type of gun because the assault shotgun and the pool stick are just stupid. the pool cue is a bat with a different skin and i think rockstar just got lazy with those weapons...